1. Field of the Invention
The present invention relates to a boot mounting structure for sealing a uniform joint or the like which mounts a propeller shaft or the like, and a method of mounting a boot.
2. Description of the Related Art
Conventionally, in a boot mounting structure for sealing grease used for improving sliding performance and durability of a uniform joint, as described in Japanese Utility Model Publication (JU-B) No. 7-7614, there is a structure in which a base portion of a boot adapter is inserted and attached to an outer wheel (a first member) of the uniform joint and an elastic boot provided in a front end portion of the boot adapter is attached to an outer peripheral portion of an inner shaft (a second member).
However, when assembling the boot provided in a front end portion thereof to the inner shaft, the boot adapter compresses a connection space between the uniform joints which the boot adapter and the boot surround in the area of an inserting and attaching length during inserting and attaching the base portion to the outer wheel from an axial direction to an extent of a fixed length, thereby increasing pressure in the connection space. When the pressure in the connection space is increased, in addition to the expansion of air due to a high temperature of the grease within the boot caused by a high speed rotation together with bending operation of the uniform joint, the boot becomes easily deformed, so that there is a risk that a peripheral portion of the boot adapter or the like and the inner shaft are interfered with each other and broken, thereby deteriorating durability,
An object of the present invention is to provide a sealing structure for a joint portion which restricts pressure increase in a connection space between a first member and a second member when attaching a boot adapter to the first member during sealing of the connection space by the boot adapter and a boot.
In accordance with the present invention, there is provided a boot mounting structure in which a base portion of a boot adapter is inserted and attached to an outer peripheral portion of a first member so as to seal a connection space between the first member and a second member and a boot provided in a front end portion of the boot adapter is inserted and attached to an outer peripheral portion of the second member, wherein the base portion of the boot adapter can form a communication passage for communicating the connection space with an external portion at least at an intermediate stage of being inserted and attached to the outer peripheral portion of the first member from an axial direction, and can shut the communication by the communication passage so as to seal the connection space at least at a final stage of the attachment.